The coin in question is a Seated Liberty Half Dime, minted in Philadelphia in 1858. This particular piece is notable for being a Proof coin, which typically indicates a higher quality of strike and finish compared to regular circulation coins. It features a denomination of 5 cents, equivalent to a nickel or half dime, and is made from silver, with a total weight of approximately 1.24 grams. The coin has a diameter of 15.5 millimeters, fitting the specifications for the series. Only 300 pieces were minted, making it a rare and collectible item among numismatists. The lack of width and height measurements suggests a simplistic representation of the coin without detailed dimensions. As part of the Seated Liberty series, this coin features the iconic image of Liberty seated on a rock, holding a shield and a liberty cap, which exemplifies the artistic style of its time. Given its low mintage and the fact that it is a proof, this 1858 Seated Liberty Half Dime holds significant value for collectors, especially those focused on historical American coinage.